Am I correct in assuming that the f5m power supplies will also be good for other First Watt kits and the Aleph jzm?
You're thinking about continuity from the green thermistor to baseplate? The standoff is metal and I double checked with a multimeter. Should be OK.
Another possibility for the audible noise is high speaker sensitivity. Are your speakers quite sensitive?
Also worth noting if you are comparing this amp and power supply to a F5 with a typical FW power supply is that the typical FW power supply has more capacitance which results in less ripple, and therefore less noise. But whether or not that is audible depends on the sensitivity of your speakers.
Also worth noting if you are comparing this amp and power supply to a F5 with a typical FW power supply is that the typical FW power supply has more capacitance which results in less ripple, and therefore less noise. But whether or not that is audible depends on the sensitivity of your speakers.
I received my DIY F5m packages today.
(amongst others.)
Just wondering, 4700 uF, it is only for sissies.
But my 27000 uF caps are a little bit bigger than fit to PS PCB.
But wait, my wacky brain started to shine brightly, this will be the solution:
(amongst others.)
Just wondering, 4700 uF, it is only for sissies.
But my 27000 uF caps are a little bit bigger than fit to PS PCB.
But wait, my wacky brain started to shine brightly, this will be the solution:
Remembering how fast they sold out earlier I eagerly pulled the trigger, thinking I'd buy the power supply alone when it becomes available. Then I saw on the PS page...
Unavailable for purchase
This product is currently unavailable for purchase directly.
And now I have concern. I hope to purchase this product directly when they have the stuff.
Yeah, I hope I'm not making a mistake waiting for the complete kit. I would be pretty salty if the first half sells out while I'm waiting for the second half lol
The "Pass DIY" chassis from Modushop arrived today and it looks awesome! I got it with the black anodized faceplate, coming from the ACA this is a behemoth!
Couple quick questions.
Couple quick questions.
- I have the dual power supplies and it looks like there is ample room for them, thoughts on going with 2 x 2218 200v transformers or one 3218 or larger, I'd love to run other projects in this chassis in the future with this power supply - Aleph jzm, Aleph J, F6m?
- The chassis back panel parts kit is out of stock, is there another easy way to get these parts, or a list of what to get?
Congrats on snagging the Limited Edition Chassis. I agree they look fantastic. Good luck with your build(s)!!!
I believe store back panel kit Includes:
Power Entry Module: Shurter 4304-6090
RCA Input: Neutrik N2FD Series (2 qty)
Speaker Terminals: Still available in the store
Hardware: M3 nuts & bolts (button cap head) [Just buy a nice affordable mixed kit on Amazon], M3 Hex Standoffs [Mixed Kit on Amazon]
Slow Blow Fuse: 5x20mm (amperage dependent on transformer(s): VA / 120V = Fuse Amp Rating) [Mixed slow blow kit on Amazon]
Addition to back panel parts needed for Balanced Input:
XLR Input: Neutrik NC3MD Series (2 qty)
Needed for dual mono:
2 Fuse Holders and Fuses (so each line/hot is fused independently)
Twice as much PSU components/parts!
Edit: Just realized the store link has pretty much all the components listed in detail.
I believe store back panel kit Includes:
Power Entry Module: Shurter 4304-6090
RCA Input: Neutrik N2FD Series (2 qty)
Speaker Terminals: Still available in the store
Hardware: M3 nuts & bolts (button cap head) [Just buy a nice affordable mixed kit on Amazon], M3 Hex Standoffs [Mixed Kit on Amazon]
Slow Blow Fuse: 5x20mm (amperage dependent on transformer(s): VA / 120V = Fuse Amp Rating) [Mixed slow blow kit on Amazon]
Addition to back panel parts needed for Balanced Input:
XLR Input: Neutrik NC3MD Series (2 qty)
Needed for dual mono:
2 Fuse Holders and Fuses (so each line/hot is fused independently)
Twice as much PSU components/parts!
Edit: Just realized the store link has pretty much all the components listed in detail.
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Thanks, missed those details at the store, thanks for the idea to get mixed kits on Amazon though, super helpful!
What do you think on single vs dual tranformers?
What do you think on single vs dual tranformers?
Dual mono...twice as much work and costs more too 😉
My dual mono F4 is nearing completion (just need to do wire management and front panel LEDs). Even after I get it playing tunes I'm not sure I could do a fair comparison since my two prior builds were Aleph Jzm and F5m with single transformers. I wouldn't know what is different sound wise because of the dual mono PSU vs the different amp designs.
I realize it's the wrong thread to post an F4 build picture, but mostly sharing to show the dual mono PSU in 5U/400 Deluxe chassis. PSU V8 boards from @rhthatcher , two Antek AS-3220 on neato 3D printed transformer seats.
My dual mono F4 is nearing completion (just need to do wire management and front panel LEDs). Even after I get it playing tunes I'm not sure I could do a fair comparison since my two prior builds were Aleph Jzm and F5m with single transformers. I wouldn't know what is different sound wise because of the dual mono PSU vs the different amp designs.
I realize it's the wrong thread to post an F4 build picture, but mostly sharing to show the dual mono PSU in 5U/400 Deluxe chassis. PSU V8 boards from @rhthatcher , two Antek AS-3220 on neato 3D printed transformer seats.
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Awesome, I saw those 3D printed mounts while reading through this thread, and you've got some of Thatcher's boards in there! I think I am going to steal that transformer configuration! Thanks for sharing that! What voltage are you runiing?
The 20V secondaries were around 28VDC rails unloaded. I'm a big fan of Randy's boards.
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Indeed. What until its built, and then try to lift it! Remember, use your back…. Or legs? 🤣
yes. But that space starts getting cramped very quickly. If going dual mono, start figuring out the layout, and cable management first, don’t be like me and mount everything then to realize its cramped to wire the amp to PSU.
🫡 good luck! It’s a bit more challenging than the ACA mini, but fun nonetheless!
You can use the power supply PCB with your choice of capacitors (30mm diameter maximum and 10mm lead spacing) and also your choice of thermistor for CRC or your choice of choke for CLC filtering.
As the F5M specified power supply is not the exact equivalent of the standard First Watt power supply, you may want to use different components/values to suit the First Watt amplifier that you are building. A simulation program such as PSUD may be helpful in choosing components/values.
As the F5M specified power supply is not the exact equivalent of the standard First Watt power supply, you may want to use different components/values to suit the First Watt amplifier that you are building. A simulation program such as PSUD may be helpful in choosing components/values.
For those patiently waiting for the power supplies to become available for purchase separately, they should be available soon.
155 of them just shipped to the warehouse today! Give it 2-3 weeks for them to arrive and then be checked in.
155 of them just shipped to the warehouse today! Give it 2-3 weeks for them to arrive and then be checked in.
I have one channel up. R6 0,72V and bias 1,45A, R6 is 0,47 ohm (measures 0,5 ohm). Before that I cooked it with bias 0,6A and R6 0,3V about 2 hours. I use 5U 500mm case.
Question about biasing. Do R8 and R9 ohm values have to be close as possible with wanted bias A and speaker DC offset? Right now it sound a little bit different and bright with vocals too present compared to the lower frequencies.
What would be a good break in period for this F5m amp? Somehow I have feeling that one mosfet is hotter than other but the voltage between R6 and R7 are the same. I use the silicon insulation pads with no paste. Do I need to make changes here to use paste or Keratherm?
Question about biasing. Do R8 and R9 ohm values have to be close as possible with wanted bias A and speaker DC offset? Right now it sound a little bit different and bright with vocals too present compared to the lower frequencies.
What would be a good break in period for this F5m amp? Somehow I have feeling that one mosfet is hotter than other but the voltage between R6 and R7 are the same. I use the silicon insulation pads with no paste. Do I need to make changes here to use paste or Keratherm?